Key Definitions Flashcards
All 6 cards in this deck
What is an allele?
An alternative version (form) of a gene.
What is a phenotype?
The observable characteristics (traits) expressed by an organism.
What is a genotype?
The combination of alleles an organism has for a characteristic.
What is the difference between a homozygous and a heterozygous genotype?
Homozygous = two identical alleles of a gene (e.g. or ); heterozygous = two different alleles (e.g. ).
What is the difference between a dominant and a recessive allele?
A dominant allele is expressed in the phenotype when only one copy is present; a recessive allele is only expressed when two copies are present.
What is a zygote?
The single cell formed when two gametes (sex cells) fuse at fertilisation.